Dash pot control device



CI R. POST DASH POT CONTROL DEVICE Original Filed March 12, 1929 Nov. 17, 1936.

2 Sheets-Sheet 1 nu I NOV. 17, 1936. c R O T DASH POT CONTROL DEVICE Original Filed Maren 12, 1929 2 Sheets-Sheet 2 /M ATTORN EY Patented Nov. 17, 1936 I iTED STATES PATENT OFFICE Application March 12,

1929, Serial No. 346,309

Renewed October 21, 1932 7 Claims.

My invention relates to a device for controlling the operation of a choke valve such as is commonly employed for controlling the mixture of fuel and air in hydrocarbon engines such as are used in automobiles. When starting a hydrocarbon engine it is the practice to operate the choke valve by partially closing the same to decrease the intake of air, in order to increase the proportion of fuel drawn in by the pistons of the motor in order to start the motor on a rich mixture. After the motor has started and no longer requires the same rich mixture necessary or desirable for the starting operation, the choke valve is opened to increase the percentage of air to fuel or, in other words, to make the mixture more lean, and on this latter mixture the motor is usually operated most of the time, or until the motor is stopped and again started. Heretofore, the choke valve has been operated by a simple rod on the dashboard of the automobile, the rod acting through a flexible wire arranged in a tube, the wire being connected with the lever arm of the choke valve. The object of the present device is to provide means adapted to be manually operated and in the case of an automobile, to be operated from the dashboard, and which, when initially actuated by hand to partially close the valve for the starting of the motor, the device will automatically effect the gradual opening of the choke valve.

Thus, the driver may, by a simple and quick operation, draw out the member on the dashboard which initially effects the operation of the choke valve, and immediately release the same, and the present device will automatically effect a gradual opening of the choke valve, so that the change in proportion of the fuel mixture will be gradual and not sudden. The time of automatic change from one condition to another may be regulated, so that the period will correspond substantially with the time elapsing between the initial starting of the motor and the time when the motor should commence to operate on a lean mixture. Changes in adjustment may be desirable for different seasons of the year, but ordinarily it will not be necessary to make adjustments from day to day.

One of the advantages of the present device is that the driver may initiate the operation of the automatic device instantly and with the least effort. In previous attempts to accomplish the automatic operation of the choke valve it has required a slow operation for initiating the device, so that there was very little advantage in the use of the same. In the present case, however, the initiating device may be drawn out very rapidly and without substantial resistance, and its return or active operation may be as slow as desired to accomplish the purpose, or it can at any point be instantly returned.

Another object of my invention is to provide a device having the above features, which is very simple and compact, and which may be mounted entirely on the dashboard, and one which may be very light in weight.

My invention is shown in two forms, in one of which the automatic opening of the choke valve is effected through the action of a spring, and the resistance of air under pressure, whereas in the second form the opening of the valve is effected through suction of the intake manifold of the engine, the movement of the parts being under the control of a partial vacuum which may be regulated by a regulating valve. In both constructions, however, the device for initiating the operation may be quickly or instantaneously operated against slight resistance, so that the driver may draw out the operating rod and immediately release it, leaving the device to its automatic operation for the opening of the choke valve.

In the drawings forming part of this application,

Figure 1 is a longitudinal, sectional view through a device embodying my invention in one form, and showing the same applied to the dashboard of an automobile,

Figure 2 is a sectional view taken on the line 2-2 of Figure 1,

Figure 3 is an elevation of the invention in a modified form,

Figure 4 is a longitudinal, sectional view of some of the parts shown in Figure 3,

Figure 5 is a perspective view of the operating rod shown in both forms of the device,

Figure 6 is a sectional view taken on the line 6--6 of Figure 4, and

Figure 7 is a sectional view taken on the line 'l-'l of Figure 6.

I will first describe the device in the form shown in Figures 1 and 2.

In this View I have shown the choke valve I of an ordinary automobile motor which valve regulates the proportion of air taken in with the fuel by the motor, and which is the valve the 50 present device is designed to control for the purpose described above. At 2 I have shown in section a portion of the dash or instrument board of an automobile. In describing the present device as applied to an automobile, I wish it to be 55 the cylinder.

understood that the invention is not limited to this particular use, as it may be employed in connection with any hydrocarbon motor. There is a cylinder 3 which is mounted on the back of the dashboard by means of brackets 4 which may be bolted to the dashboard, so that the cylinder 3 projects rearwardly from the dashboard in a horizontal position. This method of attachment is not only very simple but it makes it possible to quickly mount the device by merely drilling the necessary holes in the dash and applying screws to hold the brackets 4 in place. Preferably, the central aperture in the dash through which the operating parts hereinafter described project is lined with an eyelet 5 which aligns with the member I8.

One end of the cylinder 3 is preferably formed with an integral end wall 6 and the opposite end is provided with a closing cap I fitted over the open end of the cylinder and attached by any suitable means to form an airtight connection. This cap is provided with a boss 8 in which is fitted one end of the flexible tube 9 which tube extends downward-1y and outwardly and its opposite end is connected with a bracket I0 located adjacent the crank arm II through which. the choke valve I is operated.

There is an operating wire or rod I2 sufliciently thin to be flexible, which extends from a bracket I3 within the cylinder, and to which one end of the wire is connected, through the central aperture in the cap I, thence through the flexible tubing 9 and the opposite end of this wire is connected with one end of the lever arm I I whereby the shifting of this wire in the direction of its length may cause either the opening or closing of the choke valve I. The bracket I3 to which one end of the operating wire I2 is connected is attached by screws I4, or other means, to a piston I5 which is adapted to slide lengthwise in the cylinder 3. This piston is provided with a packing washer I6, preferably of the type used in tire pumps, the packing being in the form of a disc having a flange l1 projecting therefrom, and sliding in contact with the inner surface of This washer may be held in place on the piston by the bracket I3. The purpose of the washer is to permit the air in the cylinder to the left of the piston in Figure 1 to be compressed whenever the piston is moved from right to left in Figure 1. There is a sleeve I8 which is attached preferably by means of screw threads III at one end, in a bore in one face of the piston I5, and this sleve projects through a closefitting opening in the end. wall Ii of the cylinder, thence by loose fit through the aligned opening 5 in the dash, and the end of this sleeve projects beyond the dash where it is provided with a flange 20 to permit it to be grasped by the hand. There is a coiled spring 2| surrounding this sleeve within the cylinder and it is adapted to be compressed between one side of the piston and the end wall 6 of the cylinder, the compression increasing when the piston is moved to the right in Figure 1, storing up the energy necessary to cause the return movement of the piston.

There is a rod 22 which extends through the bore of the sleeve I8 and one end of this rod projects beyond the end of the sleeve where it is provided with a flange or handle 23 adapted to be conveniently gripped by the same hand which engages the flange 20 of the sleeve. This rod extends entirely through the sleeve I8, thence through a central aperture in. the piston I5 and an aperture. in the gasket I6 and on the end of.

this rod there is a preferably metal washer 24 which is adapted to press the valve or packing 25 against the face of the piston. There is a coiled spring 26 arranged inside the sleeve I8 and surrounding the rod 22, which is compressed between a portion of the piston and a pin 2I which projects through the rod. The rod is provided, as shown more clearly in Figure 5, with a channel 28 which opens at two points on the surface of the rod and which between these two openings extends longitudinally of the rod, as shown at 29. There is a regulating valve 3!] which I have shown arranged in a boss 3| upon the head I which may be adjusted to regulate the discharge of air from the cylinder on the left hand side of the piston as viewed in Figure 1.

The operation of this form of the invention is. as follows: Assuming that the choke valve is in fully opened position, or lying parallel with the axis of the pipe 32 at such time the piston I5 will be in its extreme left hand position, or near the head I- of the cylinder, and at such time the sleeve I8 and the rod 22 will be in their extreme left hand positions with the flange or operating members 20, 23' lying adjacent each other and near the dash. The valve 25 will be held seated against the face of the piston I5 by the action of the spring 26 which maintains a pressure upon the rod 22 toward the right in Figure 1.

If it is desired to start the motor the driver will simultaneously and with one hand press on the operating member 23 and pull outwardly on the operating member 20 and for this purpose two fingers of the hand may be used for the flange 20 and the thumb may be used on the member 23. The inward pressure on the member 23 will shift the rod 22 to the left and this will unseat the valve 25 from the face of the piston I5. One end of the port 28, 29 in the rod 22 will then be in communication with the air on the left hand side of the piston and the opposite end of this port will be in communication with the air on the right hand side of the piston. The sleeve I8, together with the piston I5, may then be quickly and easily moved to the right in Figure 1 without compressing the air on one side of the piston and rarefying it on the other, because as the piston moves during this operation any difference in pressure on opposite sides is equalized through the port 28, 29. The piston I5 may be drawn to the right nearly the full length of the cylinder or to any lesser extent, according to the time to be allowed for changing the fuel mixture. If the piston I5 is moved to its extreme right hand position its return movement will consume more time than if it is moved only partially along the cylinder 3, in which latter case the return movement of the piston will be completed in a shorter time and the choke valve will be operated accordingly. When the sleeve I8, together with the piston I5, have been moved to the right in the manner above described, the operator will release both the rod 22 and the sleeve I8 and from that time on the operation of the choke valve is under the automatic control of the device as follows: While the piston I5 was being moved to the right the spring 2| was being compressed between the piston and the head. 6 of the cylinder, storing up the necessary energy to effect the return movement of the piston.

While this movement of the piston was taking place, the rod I2 was also operating on the lever arm II to move the choke valve I into the position necessary to, decrease the air intake to the engine and thus increase the ratio of fuel to air taken in by the engine for the initial or starting operation. When the sleeve I8 and rod 22 are released at the end of the initiating operation, the rod 22 is acted upon by the spring 26 for the purpose of seating the valve 25 against the face of the piston and this prevents the passage of fluid, such as air, from one side to the other of the piston. When the sleeve I8 is released the spring 2I exerts pressure on the piston I5 and the latter starts to move toward the left in Figure 1. As it does so, it pushes on the rod I2 and the latter acts on the arm II to turn the choke valve I toward the dotted line position. As the piston I 5 moves to the left in the manner just described, the air in the cylinder on the left side of the piston is compressed, so that it offers resistance to to the movement of the piston and retards it so that a certain time is required for the piston to make its return movement. The speed at which the piston makes its return movement may be regulated by adjusting the regulating valve 30 for the purpose of controlling the release of the compressed air on the left of the piston. In this manner the device may be regulated to vary the time required for the return movement of the piston in accordance with variations in temperature between the different seasons of the year. When the piston reaches its extreme left hand position under the action of the spring 2I, the choke valve I will have been moved to the extreme open position shown in dotted lines.

From the above it will be apparent that the operator may very quickly initiate the operation of the device and with only enough effort to overcome the resistance of the spring 2I and when the rod 22 and the sleeve I8 are released the opening of the choke valve I is under the automatic control of the device and no further action on the part of the operator is required. The unseating of the valve 25 to equalize the air pressure on opposite sides of the piston permits the piston to be moved into operative position quickly and easily.

In Figures 3 to- '7 I have shown a modified form of the invention. In this construction I have shown a cylinder 35 which conforms with the cylinder 3 except that the head I in this instance has a central boss 36 for the attachment of the flexible tube 9 and for the passage of the operating rod I2. In addition, there is a boss 31 on this head to which is connected a tube or pipe 38 which latter is connected to and is in communication with the bore of the intake manifold 39 of the engine. As suction is created in this manifold by the operation of the engine, it creates a suction or partial vacuum in the tube 38 and this creates a suction in the cylinder 35 at the left of the piston I5. In this form of the device the piston I5 corresponds with the piston in the first form except that the washer 40 is attached on the opposite side of the piston to that of the washer I6 of the first form, by means of a metal washer GI which is held in place by the nut 42 on the threaded end of the sleeve I8. This latter sleeve corresponds with the sleeve I8 on the first form and one end is threaded into a bore of the piston I5. The rod 22 is also present in this construction and it has a valve 25 at one end which seats against one face of the piston, the same as in the first form.

The ports 28, 29 are also provided in the rod 22 for the same purpose as in the first form. The spring 2I referred to in connection with the first device is omitted in the modified device because the return movement of the piston is effected by means of suction instead of by spring action. The cylinder 35 is closed on the left hand side of the piston except for the pipe 38. The space on the right of the piston is closed except for a regulating valve 43 which controls the entrance of air into this end of the cylinder for regulating the return speed of the piston.

The operation of this form of the device is as follows:

When the piston I5 is at the extreme left hand end of the cylinder 35 the choke valve I will be in the dotted line position shown in Figure 3. When the engine is to be started the operator will press on the member 23 and pull on the member in the same manner as in the operation of the first form, for the purpose of unseating the valve 25 and to move the sleeve I8 to the right. When the rod 22 is thus moved in opposition to the spring 26, as shown in Figure 6, the valve 25 is unseated and the ports 28, 29 permit passage of air from one side of the cylinder to the other to eliminate resistance to the movement of the piston during the initiating operation. When the sleeve I8 has been moved with the piston to the right either the full length of the cylinder 35 or to some intermediate point, then if the members 23, 20 are released the following operations will take place. It will be understood that while the seating of the piston is occurring, the choke valve I is being moved by the rod I2 toward a closed position, thereby decreasing the proportion of air to fuel drawn in by the engine for the starting operation.

As soon as the engine is in operation a suction is created in the intake manifold 39 and this creates a suction action in the tube 38 and through this suction is created in the cylinder 35 on the left of the piston I5. This exerts a pulling action on the piston, tending to move it from right to left in Figure 4. As the piston is thus moved from right to left, it creates a suction in the cylinder at the right of the piston and this suction action has a retarding effect upon the movement of the piston so that the latter will not move suddenly to the left but will move gradually in accordance with the force exerted by the suction in the manifold. The speed with which the piston moves to the left may be regulated by adjusting the valve 43 which latter controls the admission of air into the space at the right of the piston to gradually relieve the suction action caused by the movement of the piston. In this manner the movement of the piston may be adjusted to accomplish the same purpose as was accomplished by the valve in the first described form of the invention. In other respects the device is constructed and operates the same as the first form and the parts which correspond are similarly marked in the several views of the drawings.

Having described my invention, what I claim 1. A dash pot control device including a cylinder, a piston slidable therein and adapted to control the fluid pressure on opposite sides thereof within said cylinder, said piston having a control member actuated thereby, means for effecting the operation of said piston, a manually controlled valve movable with said piston for effecting a transfer of fluid from one side to the other of said piston to reduce the resistance to the rapid movement of said piston in one direction.

2. A dash pot control device including a cylinder, a piston slidable therein and provided with control means actuated thereby, manually con.- trolled means for effecting the operation of said piston, a valve movable with said piston and manually controlled means adjacent said first manually controlled means and adapted to operate. said; valve to release the fluid in said cylinder on one side of said piston to reduce the resistance to the rapid movement of said piston in one direction.

3. A dash pot control device including a cylinder adapted to be mounted on a support to extend outwardly axially therefrom, a piston slidable in said cylinder and provided with control means actuated thereby, reciprocating means connected with said cylinder and projecting through said support to be manually operated for moving said piston, a valve movable with said piston and means for operating said valve to release the fluid pressure in said cylinder on one side of said piston to control the movement of the piston.

4. A dash pot control device including a. cylinder, a piston slidable therein and provided with control means actuated thereby, a manually operable sleeve connected with said piston for moving the latter, a rod extending through said sleeve and adapted to be manually operable in connection with said sleeve, and a valve movable with said piston and operated by said rod for releasing the fluid pressure in said cylinder in one side of said piston to reduce the resistance tothe movement of said piston in one direction.

5. A dash pot control device including a cylinder, a piston slidable therein and control means actuated thereby, a manually operable sleeve connected with said piston to operate the same, a rod extending through said sleeve and adapted to: be operated in conjunction with said sleeve, and a valve on said rod co-operating with said piston and adapted to permit transfer of fluid from one side to the other of said piston.

6. A dash pot control device including a cylinder adapted to be mounted on a support and to project endwise therefrom, a piston slidable in said cylinder, and control means actuated thereby, a sleeve connected with said piston and projecting through said support for manual operation: at the front thereof, arod extending through said sleeve and through said support to be manually operated at the front thereof, and a valve on said rodco -operating and movable with said pistonv to release the fluid in said cylinder in one side of said piston to permit rapid movement of the piston in one direction.

7. A dash pot control device including a cylinder, a piston slidable therein, and control means operated thereby, means adapted to connect said cylinder at one side of said piston with a source of vacuum supply to create a suction action on the piston whereby the latter is automatically operated in one direction, means for controlling the passage of fluid on the opposite side of said piston to retard the movement of the piston by the suction action, and manually controlled means for moving said piston into condition to-be operated by said suction means.

CHARLES R. POST. 

